Initial Conditions Computation Approximation of Nonlinear Systems using the DFEHD

A major issue in the simulation of frequency dynamics via extended harmonic domain (EHD) –based models are the incurred spurious oscillations due to the lack of correct initial conditions computation during initialization or when a step change, in either source or parameter, occurs. A recent paper has addressed the correct initialization computation for linear time-periodic systems via the dynamic flexible EHD (DFEHD); however, nonlinear systems are not applicable for this methodology. This paper addresses this issue by separating linear and nonlinear parts; then, the DFEHD is applied to the linear part, aimed at initialization purposes, to reduce the impact of the spurious oscillations dynamics. A case study is presented to demonstrate the effectiveness of the proposed approach.